Cryogenic LNG hoses is mainly used for LNG unloading interconnection between transport ships, in the process of LNG can quickly continuously the effective transmission. The FLNG transmission performance of cryogenic LNG hoses is vital role for the economy and safety of marine oil and gas development. Therefore, the detailed investigation and analysis characteristics for internal flow in cryogenic LNG hoses has important guiding significance for practical engineering design. In the work, computational fluid dynamics (CFD) is employed to build the numerical model of the internal flow field with corrugated structure inside LNG hose. Structural and process parametric studies are performed to investigate the effects of the pressure, velocity, temperature and heat transfer coefficient of the internal flow, and also the results from this model is verified against the existing experimental results. Moreover, the dimensionless correction coefficient of heat transfer and pressure-drop are obtained for the internal flow characteristics in cryogenic LNG hose. The results of this research provide a helpful support to the design of cryogenic LNG hose, and also provide some useful reference to the design of FLNG unloading process.
The rapid economic development and the urgent need of environmental protection promote the growing demand for this kind of clean energy--LNG. To bring the gas from the deep sea to land, connections are made between LNG producers and carriers or onshore. FLNG transmission device has been developed and applied in LNG transmission in recent years due to its low cost, environmental friendliness and excellent flexibility. With the wider application of floating LNG transmission devices, the existing LNG transmission technology will be more demanding. At present, the investigation of the design, manufacture and installation of LNG cryogenic transmission pipelines is a hot research area all around the world.
At present, there are two modes of LNG transportation for offshore application: rigid loading arm transportation and hose transportation. Although the unloading mode of rigid loading arm can also realize the LNG transportation, its technical conditions and some shortcomings in engineering operation cannot adapt to the extreme and complex operation conditions of LNG transportation. However, the cryogenic LNG hoses transmission technology can well meet the safety technical requirements and adapt to a variety of special operating conditions. This connection method also greatly improves the loading and unloading distance of LNG transmission, and the technical performance of a variety of cryogenic LNG hoses can be complementary (Jin et.al, 2020). Therefore, cryogenic LNG hoses has great application prospect in the field of deep-sea LNG exploitation and transportation.
